An umbilical is a group of elements that connects a subsea wellhead to a surface location providing communications, chemical transport, hydraulic control pressure, electrical controls, and/or electrical power. An umbilical typically includes a plurality of bundles of conduits that are surrounded by a protective sheath. The bundles of conduits may provide communication of fluids, light, electrical power, and/or electrical signals between the surface and a subsea location. The umbilical may include structural components, such as channel members, to secure the bundles in a radial orientation along the length of the umbilical.
An umbilical may be hundreds or even thousands of feet in length in order to reach a subsea location from the surface. The long length of the umbilical may require the insertion of strengthening members, such as steel rods, to help maintain the strength and/or integrity of the umbilical as it extends from the surface to the subsea floor. The use of steel rods and/or other metal components within the interior of the umbilical may lead to power losses and/or imbalances in power conduits traveling along the length of the umbilical. For example, a power conduit that extends the length of the umbilical may include a power triad comprised of three different power cables. The radial orientation of the power triad may be fixed along the entire length of the umbilical, which may lead to one of the power cables of the power triad being positioned closer to a metal support structure and the influence from other circuits than the other two power cables enclosed within the power conduit. The closer proximity of the power cable may lead to higher power losses than the other two power cables causing an imbalanced power loss and/or fluctuation in the power circuit as a whole. The potential for imbalanced power fluctuations between power cables of a power triad may be increased if the cross-section of the structure of the umbilical is asymmetrical.